Mid 40's is what Ewan McGregors char was suppose to be I think. Take 20 years of a hard life hiding out from the empire and by the time you reach mid 60's you could be looking a bit rough.
Not to mention the fact that he basically repped and raised the douchebag responsible for destroying the Jedi order and mercilessly slaughtering untold millions throughout the galaxy. Might wear you down just a wee bit.